Oil well derrick for use with helicopter



March 14, 1961 H. J. wooLsLAYER ErAL 2,974,760

OIL WELL DERRICK FOR USE WITH HELICOPTER Filed Feb. 21, 1958 2 Sheets-Sheet 1 HOHER J. wooLSLA yE R ALVIN 1. TURNER and CEc/L JENKINS March 14, 1961 H. .1. wooLs-LAYER ErAL OIL WELL DERRICK FOR USE WITH HELICOPTER Filed Feb. 2l, 1958 2 Sheets-Sheet 2 INVENTORS HOHER wooLsLAXR E161 .9 cALv/N L. rz/mvs United States PatC'fO OIL WELL DERRICK FOR USE WITH HELICOPTER Homer J. Woolslayer, Calvin L. Turner, and Cecil Jenkins, Tulsa, Okla., assignors to Lee C. Moore Corporation, a corporation of Pennsylvania Filed Feb. 21, 1958, Ser. No. 716,722

6 Claims. (Cl. 189-11) This invention relates to oil well derricks, and more particurarly to a derrick designed for transportation, assembly and disassembly by means of a helicopter.

' Where oil wells are to be drilled in areas that are inaccessible to trucks carrying prefabricated sections of drilling derricks, it is desirable to be able to ily the sections into the area. The most practical way of doing this is by helicopter, which can pick up a derrick section, tly it to the desired location and then set it down.

It is among the objects of this invention to provide an oil well derrick which is so formed that it can be transported in sections by helicopter, in which the sections can readily be assembled with the help of the helicopter, and which is composed largely of sections that can be lifted oif a derrick in succession as it is disassembled and then placed on top of one another in another location is an upwardly tapered portion. All of the sections are detachably connected together. Consequently, after the tapered portion has been lifted oil the straight sections of` the derrick and set on the ground, the top straight section can be removed and used at a new location Vas a bottom section, on which the remaining sections can be set by the helicopter as fast as they are removed from the derrick being disassembled until the original bottom section becomes the top straight section in the new derrick and -forms .a support for the tapered portion. Preferably, each top and bottom straight section is formed from two half sections disposed side by side. To facilitate assembly of the sections, one end of the legs of each section is plain and the Opposite end has a vertically flaring member for guiding into place the plain end of a leg of an adjoining section as it is lowered onto the section below it.

The preferred embodiment of the invention is illustrated in the accompanying drawings, in which n Fig.l l is a side view of our derrick;

Fig. 2 is a side view of the derrick turned 90;

Fig. 3 is a side View illustrating how a derrick is disassembled and flown section by section to another location Afor reassembly;

` Fig. 4 is an enlarged perspective view of the linside of the upper end ofone of the straight section legs;

Fig. 5 is an enlarged fragmentary side view taken on the line V-V of Fig. 2;

ICC.,

.Fig is an enlarged cross section taken on the line X-X of Fig. 9.

, Referring to Figs. 1 and 2 of the drawings, the derrick is formed from a plurality of superimposed prefabricated sections 1 to 10, all detachably connected together.

. Sections 1 tO 7 are straight sections wit-hvertical sides.

Fig. 6 is an enlarged fragmentary side view taken on Sections 1 and 7 are substantially identical and therefore interchangeable. Sections 2, 3, 4 and 5 are dilferent from sections 1 and 7, but they are substantially identical to one another. Section 6 is the same as these last four sections, except that it is only about half as high. Such a section would not be used if its height were not needed or if twice its height were required'. In the latter case a section like section 5 would be used in place of section 6. Sections 2 to 6 are interchangeable with one another. Tapered sections 8 and 9 form the upwardly tapered portion of the derrick. Mounted on top of them is the gin pole section 10. Also detachably mounted on top of tapered section 9 is a pair of heavy beams. 11, on which the crown block (not shown) is placed after it has been lifted up through the derrick by means of a line supported by the gin pole section.

Bottom section 1 has four corner legs 13 that are connected by upper horizontal braces 14 and 15, nwo opposite lower horizontal braces 16, and two opposite removable lower braces 17. As shown in Fig. 7, the lower ends of the legs rest on foundation plates 19 that are provided with open sided sockets 20 which receive the legs. The upper ends of the sockets are provided with upwardly ilaring stabbing guides 21 to guide the legsinto the sockets as the section is lowered into place. The legs then can be attached to the sockets by bolts 22. The upper ends of the legs of the lower section are provided with similar stabbing guides 23, such as shown in Fig. 4, so that the plain lower ends of the legs of section 2 will be directed down onto the upper ends ofthe legs 13. The legs of sections 2, 3, 4, 5 and 6 are all plain at their lower ends and provided with stabbing guides 25 at their upper ends.

Section 7, being like section 1, has stabbing guides 23 at the upper ends of its legs 13 for receiving the downwardly bent lower ends of the inclined legs 28 of tapered section 8, as shown in Fig. 6. Unlike the sections below it, the upper ends of inclined legs 28 are plain and extendup into stabbing guides 29 on the lower ends of inclinded legs 30 of upper tapered section 9 (Fig. 5). lf the stabbing guides were on legs 23, the walls of the guides would be substantially vertical, unless made specially, and therefore would notv serve their intended function satisfactorily. As shown in Fig. 8, the lower end of the gin pole section 10 is bolted down to brackets 31 projecting laterally from the upper ends of the legs of section 9, and beams 11 also rest on those legs and have their tops bolted to brackets 32 attached to the sides of gin pole legs 33.

As sections 1 and 7 are large and heavy and therefore may weigh too much to be carried safely by helicopter, each of these sections is divided vertically into two half sections 34. Each half section includes two legs 13 a connecting top brace 14, a removable bottom brace 17, and a half of brace 15 and a half of brace 16 at each end of braces 14 and 17. These half sections are set down separately and then fastened together and to their common support. The lower inner ends of the halfsec- -tions of section 7 are supported by brackets 35 secured to them and the top of the upper cross brace of section 6, as shown in Figs. 9 and 10. The lower inner ends of the half sections of section 1 may be detachably connected by a suitable splice bar (not shown).

When it is desired to transport this derrick to, another location by helicopter, the crown block is lowered by the gin pole to the ground and then Vthe helicopter picks up the gin pole section 10 with the two beams 11 andv sets them on the ground beside the derrick or irst flies them to the new we'll location. The helicopter then lifts ottupper tapered section 9 `and does the same thing with it, although if the combined weight of sections 9 andlt) and beams 11 is not too great for the helicopter, they can all be removed as a single unit. Lower tapered section 8 then is lifted oi the derrick by the helicopter and deposited on the ground. These operations are illustrated in Fig. 3,

A different lprocedure is now followed' for the rest of the derrick. The'two halves of section 7 are disconnected from each other and supporting section 6, and then one half section 34 is klifted from the derrick and own to the new location and set in place on a base that has beenprepared. The helicopter then returns and brings back the other half of section 7 and lowers it onto the base, wherethe two half sections are bolted in placeand connected together. Each half section is prevented by its brace 17 from collapsing during ight, but generally braces 17 are removed afterr mounting on the base so that the braces will not obstruct the floor. The helicopter then picks up` straight section 6 and places it on section 7, which is now the bottom section as shown in Fig. 3. Sections 5, 4, 3 and 2 are lifted and own in succession to the new location and placed ,in that order on top of 'one another to build up the new derrick. Braces 17 are bolted in place at the bottoms of the halves 34vof section 1, and then one half section is iiown from the old derrick base and set on top of section 2. The other half of section 1 is then de- .posited beside it on section 2 and both half sections are secured in place. The straight portion of the new derrick now has the same appearance as the old one, but sections 1 to 7 are now inrreverse order, with section 1 at-the top and section 7 at the bottom. Section 8 is next picked up from the ground and deposited on section 1, after which sections 9 and 10 are lifted and Set on top of section 8. f course, as the various sections are put in position, they are bolted in place at the corners. As soon as the crown block has been raised by the gin pole onto the beams, the derrick is ready to start operating.

The derrick sections are lifted and carried by a helicopter by means of a sling (Fig. 3) suspended from the helicopter. The sling'preferably includes four lines 4t? with their lower ends held apart by crossed spreader rods or bars 41. When the sling is lowered over the derrick by a hovering helicopter, a man up in the derrick at each corner grabs the nearest Ilower corner of the sling and pins it to a perforated bracket 42 (Fig. .4) welded lto the inside of the upper part of the nearest leg of the derrick section that happens to be uppermost. The men then descend below that section and the helicopter lifts it and ies away. At its destination, the section is lowered by the sling onto an underlying section. The sling then is disconnected from brackets 42. In emergencies, the sling can be quickly released from the helicopter in va well known manner by the at one location and assembled at another, because most of the derrick sections do not need to be set on the ground but can be moved directly from one derrick to .the other. The use of a helicopter in dismantling and assembling a derrick also is a great help in view of the Vfact that it permits the use of prefabricated sections without the necessity of a crane.

- According to the provisions of the patent statutes, we have explained the principle of our invention and have illustrated and described what we now consider to represent its best embodiment. However, we desire to have it understood that, within the scope of the appended claims, the invention may befpracticed otherwise than as specilically illustrated and described.

We claim: i

l. An oil well derrick adapted to be transported in sections by helicopter and assembled by it, the derrick comprising a plurality of superimposed prefabricated straight sections having vertical sides, the bottom section having a side provided with a drill pipe access opening, the top and bottom straight sections being substantially identical and interchangeable and the intermediate sections having a different construction than said top and bottom sections and being interchangeable with one another only, and means detachably connecting all of said sections together, whereby the top straight section can be removed and used at a new location as a bottom section on which' the remaining sections can be set by helicopter as fast as they are removed from the derrick being disassembled until the original bottom section becomes the top straight section in the new derrick.

2. An oil well Vderrick adapted to be transported in sections by helicopter and assembled by it, the derrick comprising a plurality of superimposed prefabricated straight sections having vertical sides, the bottom section having a side provided with a drill pipe access opening, the top and bottom sections being substantially identical and interchangeable and the intermediate sections having a different construction than said top and bottom sections and being interchangeable with one another only, each top and bottom straight section being formed from two half sections disposed side-by-side, and means detachably connecting all of said sections together, whereby the top half sections can'be removed and used at a new location as a bottom section on which the. remaining Sections can be set by helicopter in reverse order. Y

3. An oil well derrick according to Aclaim l, in which each section has a plurality of legs connected by braces, one end of the legs of each section being plain and the opposite end having vertically flaring members for guiding into place the plain ends of the legs of an adjoining section when one section is lowered onto another in assembling the derrick.

' 4. A skeleton tower adapted to be transported by helicopter and assembled by it, the tower comprising a plurality of Prefabricated sections disposed on top of one another, each section having a plurality of legs-in end-toend engagement with the legs of the adjoining sections, one end of the legs of each section being plain, vertically daring stabbing guides secured to the opposite end portion of the legs of some sections and receiving the plain ends of the legs of an adjoining section, meansremovably fastening said plain ends of each section in said stabbing guides of an adjoining section, the top and bottom sections being substantially identical and interchangeable and the intermediate sections having a different construction than said top and bottom sections andY beingV interchangeable with one another only, and brackets projecting inward from the upper ends of the section legs adapted to receive a sling suspended from a.v helicopter, whereby a section canfbe raised after being disconnected from the section below it. V p

' 5. A rectangular oil well derrick adapted to be transported in sections by helicopter and assembled by it, the derrick comprising a plurality of superimposed prefabricated straight sections having vertical sides, the top and bottom sections being substantially identical and interchangeable and the intermediate sections having a diierent construction than said top and bottom sections and being interchangeable with one another only, each top and bottom straight section being formed from two -half sections disposed side-by-side, each half section including two cornerv legsV connected at top and bottom by horizontal braces with inclined braces converging upwardly from the bottoms of the legs to the center of the upper brace, the lower brace being removable, and means detachably connecting all of said sections together, whereby the top half sections can be removed and used at a new location as a bottom section.

6. An oil well derrick according to claim 5, in which each of said half sections also includes upper and lower half braces projecting about half way across the derrick from the top and bottom of Said legs perpendicularly to said horizontal braces, with inclined braces holding said half braces parallel.

References Cited in the le of this patent UNITED STATES PATENTS Young `Tuly 2, 1929 Dunaway Mar. 19, 1940 Bates Sept. 22, 1942 Cohen Oct. 16, 1945 Boschen Nov. 6, 1951 Woolslayer Sept. 28, 1954 Moyer Oct. 2, 1956 Terrell Oct. 28, 1958 Woolslayer Dec. 9, 1958 

